Papershow: A truly portable magic whiteboard?

I've been playing with a demo version of Papershow. While it at first appeared as flakey as a bad case of dandruff, it turned out a weak battery in the pen was at fault.
Wish the instructions also included: First, check a battery is installed...
Anyway, once I got up and running I found it relatively user-friendly and cool enough to make me smile on my first use. It has that sense of "Magic! It works!" that makes you grin.

You get to use normal paper (you can use theirs which have buttons printed on in the right places, too - I imagine photocopying these would work into the future(?). There's a usb dongle which connects via bluetooth to the pen.
I found it worked from at least eight metres away.
And it is portable with a capital P. The usb dongle carries the software and any ppt's you may wish to play with too (you have to print out the powerpoint via the software in order for it to work on powerpoints too, it seemed to me).
That means you can take the dongle the pen and some paper with you and use anyone's pc.

It solves a problem. Often when I present I would like to draw a quick diagram or illustration to clarify a point or answer a question. This allows exactly that.

It also allows you to replace flip-chart notes with something veryone can share and take-away.

They say: "Developed by John Dickinson, the stationery company behind the Black and Red notebooks, Papershow takes the concept of an interactive whiteboard to another level. Using just a pen, a USB dongle, and a pad of special notepaper, you can edit presentations on the fly as easily as if you were scribbling notes. It is an excellent visual aid, an effective way to increase interactivity, and the best solution for recording meeting notes."